Anti-viral vaccines expressed in plants

Abstract

The anti-viral vaccine of the present invention is produced in transgenic plants and then administered through standard vaccine introduction method or through the consumption of the edible portion of those plants. A DNA sequence encoding for the expression of a surface antigen of a viral pathogen is isolated and ligated to a promoter which can regulate the production of the surface antigen in a transgenic plant. This gene is then transferred to plant cells using a procedure that results in its integration into the plant genome, such as through the use of an Agrobacterium tumenfaciens plasmid vector system. Preferably, the foreign gene is expressed in an portion of the plant that is edible by humans or animals. In a preferred procedure, the vaccine is administered through the consumption of the edible plant as food, preferably in the form of a fruit or vegetable juice which can be taken orally.

We claim: 
     
       1. A transgenic tobacco plant comprising a DNA sequence encoding a recombinant hepatitis B viral surface antigen protein, wherein said plant is capable of synthesizing a recombinant hepatitis B viral surface antigen protein which assembles into antigenic particles. 
     
     
       2. A method for producing an antigenic composition comprising the steps of: constructing a plasmid vector or a DNA fragment by operably linking a DNA sequence encoding a hepatitis B viral surface antigen protein which protein is capable of assembling into antigenic particles, to a tobacco plant-functional promoter capable of directing the expression of said protein--encoding DNA sequence in a tobacco plant;   transforming a tobacco plant cell with said plasmid vector or DNA fragment; and,   recovering said particles.   
     
     
       3. The method of claim 2 further comprising the step of; prior to recovering said particles, regenerating a transgenic tobacco plant from said transgenic tobacco plant cell.   
     
     
       4. The method of claim 2 wherein said recovery step further comprises obtaining an extract of said plant cell. 
     
     
       5. The method of claim 3 wherein said recovery step further comprises harvesting at least a portion of said transgenic plant. 
     
     
       6. The method of claim 2 wherein said plant cell is transformed utilizing an Agrobacterium system. 
     
     
       7. The method of claim 6 wherein said Agrobacterium system is an Agrobacterium tumefaciens-Ti plasmid system. 
     
     
       8. The method of claim 2 wherein said plant cell is transformed utilizing a microparticle bombardment transformation system. 
     
     
       9. The method of claim 2 wherein said plasmid vector is a binary vector. 
     
     
       10. The method of claim 2 wherein said plasmid vector is an integrative vector. 
     
     
       11. The method of claim 2 wherein said plasmid vector is pB121. 
     
     
       12. The method of claim 2 wherein said plant cell is transformed by microinjection. 
     
     
       13. The method of claim 2 wherein said plant cell is transformed by polyethylene glycol mediated uptake. 
     
     
       14. The method of claim 2 wherein said plant cell is transformed by electroporation.